The present invention relates to the field of drilling. More specifically the invention relates to drilling holes in the ground in confined spaces, hazardous conditions or even under water where the drilling rig's power plant may create a noise, vapor, flammability, explosive or contamination problem.
In many field of endeavor it is necessary to drill holes in the ground. Borings are needed for soil and groundwater investigations, for mineral exploration, or for blast holes. Major users of drilling rigs are the geotechnical and environmental industries. Others are the mineral and oil exploration industries. If the location desired for drilling is outdoors, such as in mineral exploration, one can transport a portable drill rig to or erect a drill rig at the desired location.
Examples of portable drill rigs abound in the patent literature. U.S. Pat. No. 3,682,253 describes a mobile mounting frame for rock working tools having universally movable tool positioning and operatively supporting means. U.S. Pat. No. 3,088,531 shows a self propelled rock drill cruiser, providing stability on uneven terrain, where the rock drill positioning boom is hydraulically operated and the drill is actuated by compressed air. U.S. Pat. No. 3,565,184 is for a drill rig comprising a foldable two-part boom structure mounted with one end at a mobile chassis for lateral and vertical swinging. A feed bar for a rock drill is mounted at the outer end of the boom structure for universal pivoting. U.S. Pat. No. 4,088,289 shows a portable drill rig having a pair of telescoping struts which are connected at their upper ends to an elongated mast support member. This drill rig includes a crawler under-carriage. U.S. Pat. No. 3,664,436 shows an adjustable mounting for a rock drill having a feed tilt mechanism. This mechanism is mounted on a crawler track. U.S. Pat. No. 2,854,251 describes an improved mobile rock drill rig having an improved adjustable supporting structure, which is mounted on an improved mechanized crawler which can traverse rough terrain. U.S. Pat. No. 2,842,340 is drawn to an improved drill carriage mounted on endless trackways that form traction members for the carriage and are driven by air operated motors. U.S. Pat. No. 3,722,601 shows a drill rig with a detachable crawler. U.S. Pat. No. 3,642,075 covers a rock drilling vehicle adapted to have one or more rock drills mounted on it. The vehicle has places for mounting power plants and storing operating fluids.
Many portable drill rigs are commercially available. Examples are the models B-80, B-57 and B-61 HDX manufactured by Mobile Drilling Company, Inc. of Indianapolis, Indiana; and the models A-200, A-300, and T3W manufactured by Ingersoll Rand. Each of these has a drilling system mounted on the rear of a flat bed truck, so that drilling can be conducted off the end of the truck. The drilling system can be folded down, typically over the cab of the truck, for transportation from one drilling site to another.
Typically the drill rigs described above are tall, noisy, generate objectionable fumes and, because they include an internal combustion engine, are inherently unsafe in flammable or explosive atmospheres or in confined spaces with limited access or poor air circulation. They need to be tall to handle the sampling tools used as well as the drill pipe and augers used in the drilling operation. These are not major obstacles if drilling can be done outdoors. If the location desired for drilling is outdoors on relatively level solid ground, one can transport a portable drilling rig to any desired location.
There are also several examples of remotely controlled under water equipment. U.S. Pat. No. 3,626,963 shows an underwater bulldozer that can be suspended from a ship. Electrical control signals are transmitted from a control panel, carried by a diver, to the bulldozer. U.S. Pat. No. 5,042,959 describes an undersea operating system, for construction, moving of rocks etc., comprising a machine having a vehicle and an articulated arm, which is suspended from and controlled by a ship. Hydraulic power is provided to the machine from the ship via a special cable. Neither of these inventions is designed for underwater drilling, however.
Frequently, in geotechnical/environmental applications, it is necessary to drill in confined places, such as inside a building. Here, getting the rig to the desired location is a major problem. There are several rigs designed for drilling in confined locations. One such rig is described in U.S. Pat. No. 3,784,159. This patent describes a drill rig comprising a mobile chassis, rock drill supporting means and hydraulic jacks. Another such rig is shown in U.S. Pat. No. 3,490,546. This patent shows a transportable boring machine constructed to have a relatively short transport position height so that the machine may ne moved through relatively small tunnels. These rigs may be movable through small tunnels but they still need considerable mast height for drilling. Furthermore, fumes and noise can render the location hazardous for operators and the fumes have been known to affect boring monitoring equipment.
There are even hand held drills such as those shown in U.S. Pat. Nos. 4,116,284 and 3,705,632. The former is powered by a separate power plant which rolls after the operator on wheels. The latter is designed to be operated remotely by the electrical system of a snowmobile. Hand held drill rigs such as these can be underpowered, thus making the drilling task difficult and time consuming.
Development of a drill rig which can reach into locations which are confined or may have limited access, has sufficient power, and can drill without any undue noise, fumes, or ignition potential would represent a great improvement in the drilling field and would satisfy a long felt need of the geotechnical/environmental industry. Development of a self propelled drill rig which had a remote source of power would likewise represent a great improvement in the underwater drilling field. There is substantial demand for such a drilling rig that can perform all of the above functions, yet can also serve the more mundane tasks of prior art drilling rigs. Versatility and economy are paramount considerations in the selection of a drilling rig.